Skip to content

Commit 271c594

Browse files
juangjjuangj
committed
Use the TouchEvent constructor.
TouchEvent.initTouchEvent was deprecated in Chrome 49, and removed in Chrome 54, because it was really quite broken. Chrome still falls under bot.events.BROKEN_TOUCH_API_ for now, but having the TouchEvent code available sets the stage for switching when convenient.
1 parent c65a338 commit 271c594

1 file changed

Lines changed: 78 additions & 9 deletions

File tree

‎javascript/atoms/events.js‎

Lines changed: 78 additions & 9 deletions
Original file line numberDiff line numberDiff line change
@@ -445,6 +445,19 @@ bot.events.KeyboardEventFactory_.prototype.create = function(target, opt_args) {
445445

446446

447447

448+
/**
449+
* Enum representing which mechanism to use for creating touch events.
450+
* @enum {number}
451+
* @private
452+
*/
453+
bot.events.TouchEventStrategy_ = {
454+
MOUSE_EVENTS: 1,
455+
INIT_TOUCH_EVENT: 2,
456+
TOUCH_EVENT_CTOR: 3
457+
};
458+
459+
460+
448461
/**
449462
* Factory for touch event objects of a specific type.
450463
*
@@ -506,22 +519,61 @@ bot.events.TouchEventFactory_.prototype.create = function(target, opt_args) {
506519
return touches;
507520
}
508521

509-
function createTouchList(touches) {
510-
return bot.events.BROKEN_TOUCH_API_ ?
511-
createGenericTouchList(touches) :
512-
createNativeTouchList(touches);
522+
function createTouchEventTouchList(touchListArgs) {
523+
/** @type {!Array<!Touch>} */
524+
var touches = goog.array.map(touchListArgs, function(touchArg) {
525+
return new Touch({
526+
identifier: touchArg.identifier,
527+
screenX: touchArg.screenX,
528+
screenY: touchArg.screenY,
529+
clientX: touchArg.clientX,
530+
clientY: touchArg.clientY,
531+
pageX: touchArg.pageX,
532+
pageY: touchArg.pageY,
533+
target: target
534+
});
535+
});
536+
return touches;
537+
}
538+
539+
function createTouchList(touchStrategy, touches) {
540+
switch (touchStrategy) {
541+
case bot.events.TouchEventStrategy_.MOUSE_EVENTS:
542+
return createGenericTouchList(touches);
543+
case bot.events.TouchEventStrategy_.INIT_TOUCH_EVENT:
544+
return createNativeTouchList(touches);
545+
case bot.events.TouchEventStrategy_.TOUCH_EVENT_CTOR:
546+
return createTouchEventTouchList(touches);
547+
}
548+
return null;
549+
}
550+
551+
// TODO(juangj): Always use the TouchEvent constructor, if available.
552+
var strategy;
553+
if (bot.events.BROKEN_TOUCH_API_) {
554+
strategy = bot.events.TouchEventStrategy_.MOUSE_EVENTS;
555+
} else {
556+
if (TouchEvent.prototype.initTouchEvent) {
557+
strategy = bot.events.TouchEventStrategy_.INIT_TOUCH_EVENT;
558+
} else if (TouchEvent && TouchEvent.length > 0) {
559+
strategy = bot.events.TouchEventStrategy_.TOUCH_EVENT_CTOR;
560+
} else {
561+
throw new bot.Error(
562+
bot.ErrorCode.UNSUPPORTED_OPERATION,
563+
'Not able to create touch events in this browser');
564+
}
513565
}
514566

515567
// As a performance optimization, reuse the created touchlist when the lists
516568
// are the same, which is often the case in practice.
517-
var changedTouches = createTouchList(args.changedTouches);
569+
var changedTouches = createTouchList(strategy, args.changedTouches);
518570
var touches = (args.touches == args.changedTouches) ?
519-
changedTouches : createTouchList(args.touches);
571+
changedTouches : createTouchList(strategy, args.touches);
520572
var targetTouches = (args.targetTouches == args.changedTouches) ?
521-
changedTouches : createTouchList(args.targetTouches);
573+
changedTouches : createTouchList(strategy, args.targetTouches);
522574

523575
var event;
524-
if (bot.events.BROKEN_TOUCH_API_) {
576+
if (strategy == bot.events.TouchEventStrategy_.MOUSE_EVENTS) {
525577
event = doc.createEvent('MouseEvents');
526578
event.initMouseEvent(this.type_, this.bubbles_, this.cancelable_, view,
527579
/*detail*/ 1, /*screenX*/ 0, /*screenY*/ 0, args.clientX, args.clientY,
@@ -532,7 +584,7 @@ bot.events.TouchEventFactory_.prototype.create = function(target, opt_args) {
532584
event.changedTouches = changedTouches;
533585
event.scale = args.scale;
534586
event.rotation = args.rotation;
535-
} else {
587+
} else if (strategy == bot.events.TouchEventStrategy_.INIT_TOUCH_EVENT) {
536588
event = doc.createEvent('TouchEvent');
537589
// Different browsers have different implementations of initTouchEvent.
538590
if (event.initTouchEvent.length == 0) {
@@ -548,6 +600,23 @@ bot.events.TouchEventFactory_.prototype.create = function(target, opt_args) {
548600
touches, targetTouches, changedTouches, args.scale, args.rotation);
549601
}
550602
event.relatedTarget = args.relatedTarget;
603+
} else if (strategy == bot.events.TouchEventStrategy_.TOUCH_EVENT_CTOR) {
604+
var touchProperties = /** @type {!TouchEventInit} */ ({
605+
touches: touches,
606+
targetTouches: targetTouches,
607+
changedTouches: changedTouches,
608+
bubbles: this.bubbles_,
609+
cancelable: this.cancelable_,
610+
ctrlKey: args.ctrlKey,
611+
shiftKey: args.shiftKey,
612+
altKey: args.altKey,
613+
metaKey: args.metaKey
614+
});
615+
event = new TouchEvent(this.type_, touchProperties);
616+
} else {
617+
throw new bot.Error(
618+
bot.ErrorCode.UNSUPPORTED_OPERATION,
619+
'Illegal TouchEventStrategy_ value (this is a bug)');
551620
}
552621

553622
return event;

0 commit comments

Comments
 (0)